Bruce Beveridge, president of the Law Society of Scotland, said: "She was hugely influential and committed to the causes she passionately believed in, such as Scottish independence and assisted suicide legislation, and she will sadly now not see the outcome of these two debates.

"She was a vibrant and important figure in Scottish public life and a staunch supporter of the Scottish legal profession, shown by being a judge for many years for the Scottish Legal Awards.

"She will be very sadly missed and her loss will be keenly felt across the political spectrum."

A classic image of Margo overlooking Edinburgh, a place where she would forge her reputation as one of the finest politicians in Scotland

5:01 pm

"Margo's passing sees a bright light, and one of the biggest personalities and characters of Scottish modern political life, go out.

"Her sense of humour, passion, integrity and unflinching desire to speak truth to power, meant she came as close to a political treasure in Scotland as I think it is possible to be."

Scottish Conservative leader Ruth Davidson said: "Forthright and determined, she was also humorous and warm - passionate about issues, about the parliament itself and about the better Scotland she wanted to help build.

"She sat as an independent, and independent she was - independent of thought, independent of mind and independent of spirit."

Johann Lamont, Scottish Labour leader

4:43 pm

Scottish First Minister Alex Salmond, leader of the SNP, hailed her as "one of the great rallying figures of Scottish nationalism".

"From her Govan by-election victory in 1973 she had a profound role in Scotland's home rule journey," he said.

"Very few politicians are recognised and known to the public by their first name - Margo was. Even fewer have the profile and talent to be elected comprehensively as an independent candidate - Margo had.

"I saw her only last week to talk tactics on the independence referendum. Despite great physical infirmity, she dispensed wise advice and her enthusiasm and commitment to the independence cause was bright and undimmed."

4:41 pm

Blair Jenkins, chief executive of Yes Scotland, said: "There will never be another Margo. She was held in great affection and respect by everyone who came in contact with her, regardless of their political views.

"She was a very distinguished parliamentarian but, much more than that, Margo will be remembered for her great humanity and concern for her fellow citizens.

"She was one of the best-loved champions of the national movement for independence, a cause for which she campaigned vigorously and very passionately for all of her adult and political life."

She added: "To be known and recognised by a first name is reserved to very few. But everyone knew Margo. She had a rare skill in being able to translate political speak into language we could all understand.

"She was a sparkling jewel in the Scottish Parliament, her contributions were incisive, intelligent and always got to the heart of the issue under discussion.

"Margo cared about people and, in return, they cared about her.

"My heartfelt sorrow and our condolences from across the Parliament go out to her husband and her family at this time."

Politicians from all parties have paid tribute to her, with Scottish Secretary Alistair Carmichael saying: "Scottish politics will be poorer, less colourful and less interesting without Margo MacDonald.

"She was a woman of remarkable personal strength and political conviction."

Scottish Labour leader Johann Lamont said: "Margo's passing sees a bright light, and one of the biggest personalities and characters of Scottish modern political life, go out.

"Her sense of humour, passion, integrity and unflinching desire to speak truth to power meant she came as close to a political treasure in Scotland as I think it is possible to be."

Scottish Tory leader Ruth Davidson described Ms MacDonald as being "a huge figure in Scottish politics and a complete one-off".

She added: "She sat as an independent, and independent she was - independent of thought, independent of mind and independent of spirit.

"From prostitution to assisted suicide, she was willing to champion difficult, challenging and morally complex issues to ensure they got the parliamentary consideration they deserved."

Scottish Liberal Democrat leader Willie Rennie said: "Margo was a force of nature in Scottish life. The affection for her transcends party politics and political parties.

"Her personal kindness and professional charm will be missed in the Parliament, throughout the Lothians, and far wider."

Katherine Crawford, director for Parkinson's UK in Scotland, said: "Put simply, Margo MacDonald was an inspiration to all she met and I am deeply saddened by her passing.

"It has been our honour to work with Margo over the last few years and we could not help but admire her bravery in living with the daily challenges of Parkinson's.

"Margo had immense heart, and her undeniable intelligence, personality and humour touched all of those she met."

Details of Ms MacDonald's funeral will be announced next week.

4:22 pm

Her husband, former SNP deputy leader Jim Sillars, said: "My wife Margo MacDonald died peacefully at home surrounded by her family today at 1.10pm. She leaves a void in our lives which will be impossible to fill and her death robs the Scottish nation of one of its greatest talents. She was without question the most able politician of her generation. Today the brightest light in the Scottish political firmament has gone out.

Mr Sillars said his wife's legacy would "speak for itself", adding: "She supported and inspired generations of idealists and campaigners who, like her, wanted Scotland to take its place in the world.

"Her talent acted like a magnet and she gave her time so freely to so many for so long."

While he said many would mourn her, he added: "The pain of loss will be borne most of all by those at the heart of her life - her children and her grandchildren. We will do all we can to honour her memory."

Ms MacDonald, who had two daughters, Zoe and Petra, first came to national prominence when she famously won the Glasgow Govan by-election for the SNP in 1973, triumphing in what had been regarded a Labour stronghold.

At the time she was dubbed the "blonde bombshell", but she failed to hold on to the seat in the 1974 general election.

She returned to elected politics in 1999 when she became a list MSP for the SNP in the Lothian region in the Scottish Parliament.

After being placed low down on the party's list for the area for the 2003 election, she decided to stand as an independent, and was elected in 2003, 2007 and again in 2011.

The Parkinson's sufferer campaigned for assisted suicide to be legalised, bringing two Member's Bills before Holyrood.

The first proposal was voted down by MSPs in 2010, with Ms MacDonald going on to launch a second attempt to change the law in 2013.

Her Assisted Suicide (Scotland) Bill will continue to go through Holyrood, with Green MSP Patrick Harvie now spearheading the proposed legislation.

While the death of a regional MSP usually results in a new member being taken from the party's list, this will not happen in Ms MacDonald's case as she was an independent. Her seat at Holyrood will instead remain vacant until the 2016 Scottish Parliament election.

First Minister Alex Salmond hailed her as "one of the great rallying figures of Scottish nationalism".

He added: From her Govan by-election victory in 1973 she had a profound role in Scotland's home rule journey. Very few politicians are recognised and known to the public by their first name - Margo was. Even fewer have the profile and talent to be elected comprehensively as an independent candidate - Margo had.

"I saw her only last week to talk tactics on the independence referendum. Despite great physical infirmity, she dispensed wise advice and her enthusiasm and commitment to the independence cause was bright and undimmed."